1. Diabetes Centre Isala Zwolle The Netherlands
2. Innofeet Zwolle The Netherlands
3. Department of Internal Medicine University Medical Centre Groningen Groningen The Netherlands
4. University of Groningen Groningen The Netherlands
5. Medical Research Group Langerhans Ommen The Netherlands
6. Laboratory of Medical Microbiology and Infectious Diseases Isala Zwolle The Netherlands
7. Department of Internal Medicine Gelre Hospital Apeldoorn The Netherlands